Datsun Roadster Forum-311s.org

Hi guys! Need a little help...I have a 1968 spl311 and someone has switched the engine prior to me buying the car. It appears to be an L series. It has a 2 barrell weber on it. They have cut away what appears to be the frame at the bottom to make clearance for the what I think is the oil pump. Can anyone help me find numbers on this engine to help me identify it?
Thanks!

Hey Ramfan14,
On the passenger rear side of the engine there is block id stamp. It is located just below the head surface and below #4 spark plug. There is a machined flat surface with the id on it. It should say L16, L18 or L20B. It may be rusty or covered with paint, hit it with some emery cloth or a razor blade on end to scrape it clean to read.

When you say "cut away ...frame", you mean chassis or body metal? And, which side was cut? The driver's side (carbs side) inner fender panel has been cut by some to access the starter which is hard to access with the manifold in place........

I can get the serial # off, which is right next to the # you guys are talking about. I appears to be 423933...and I am not positive on the 33. The serial # off the transmission is 7405787 and the carburater # is 11FFEA9F8. The cut away portion is on the frame on what I would consider the cross member located directly below the water pump...that would be on the passenger side. Just a note, the carburator and the starter are on opposite sides...in other words the starter is on the passenger side. Thank you for you help!

Maybe a picture of the motor would help too.

A picture would definitely help.
But still need to know the designation before the 423933 number, it should be L16, L18 or L20b.
It's kindof like SPL311 versus SRL311 in the VIN for the Roadster, the numbers after only represent when it was made. Hope this helps.